Minimum character region determining apparatus and method, character string generating apparatus for generating a character string according to the minimum character region determining method

ABSTRACT

A squared character region for a letter is partitioned into three partitive regions arranged in a longitudinal direction to partition the letter. Thereafter, a right fit position of a portion of the letter placed at the most right side in a partitive region is determined for each of the partitive regions. Therefore, the right fit positions indicate right shape features of the letter. Thereafter, a right minimum fit position indicating the most right position among the right fit positions is determined, a right proportional position is regarded as a right kerning position in a partitive region relating to the right minimum fit position, and another right kerning position is set between the right minimum fit position and the right fit position for each of remaining partitive regions. Also, a left kerning position is determined in the same manner for each of the partitive regions. A minimum character region for the letter is defined as an enclosed region specified by the right and left kerning positions, and letters of a character string are put close together by connecting minimum character regions determined for the letters in series on condition that the minimum character regions are not overlapped each other.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to minimum character region determiningapparatus and method, which is utilized in a printing apparatus forprinting a character string on a printing medium and in a displayingapparatus for displaying a character string on a displaying unit, inwhich a minimum character region required for a character isautomatically determined. Also, the present invention relates to acharacter string generating apparatus in which letters of a characterstring are put close together to arrange the letters at appropriatecharacter pitches on condition that the minimum character regions forthe letters determined by the minimum character region determiningapparatus according to the minimum character region determining methodfor the purpose of printing out the character string on the printingmedium or displaying the character string on the displaying unit.

2. Description of the Prior Art

There are many types of character pitch setting technique such astraditional-, kerning-, touching- and overlapping-techniques,. In caseswhere characters in a character string are arranged in equal intervalsaccording to the traditional character pitch setting technique,characters adjacent to each other appear to be distantly or closelyarranged, in dependence on types of the characters. In particular,whether letters of the English alphabet adjacent to each other appear tobe distantly or closely arranged considerably depends on types of theletters. Therefore, it is required to determine a character pitch (or akerning value) for each pair of characters adjacent to each other whileconsidering types of the characters according to the kerning characterpitch setting technique. In the kerning technique, a character pitch isset to a kerning value less than a character size, and a characterintrudes into a squared character region of an adjacent character oncondition that the character does not touch the adjacent character.

In a first conventional technique, a fixed value is adopted as acharacter pitch between arbitrary characters adjacent to each other.However, because characters in a character string are equally spaced ata fixed pitch, pitches of the characters appear to differ from eachother, so that there is a drawback that a reader feels uncomfortable.

In a second conventional technique, to change a character pitch betweena fore character and a rear character adjacent to each other, aproportional pitch predetermined for a type of the fore character isadopted as the character pitch. However, because a proportional pitch ispredetermined for each of the character types, the character pitch for afront character is uniformly determined to a corresponding proportionalpitch regardless of a type of a rear character. Therefore, characterpitches in a character string appear to differ from each other, so thatthere is the same drawback that a reader still feels uncomfortable.

In a third conventional technique, to determine a character pitchbetween characters adjacent to each other for each of types of thecharacters, a character pitch is predetermined for each of thecombinations of character types. In this case, a high-grade computer isutilized to read a character pitch stored in a memory for each pair ofcharacters utilized in a character string. However, because it isrequired to store a large number of character pitches corresponding to alarge number of combinations of character types, a large capacity typememory is required of a computer. Therefore, character pitches definedamong alphanumeric characters are limitedly stored in the large capacitytype memory. Also, even though character pitches in alphanumericcharacters are utilized, there is a drawback that a high-grade typecomputer is required.

2.1. Previously Proposed Art

To solve the above drawbacks, a letter distance data generatingapparatus has been disclosed in a Published Unexamined Japanese PatentApplication No. 361077 of 1992 (H4-361077). In this application,features of a letter outline are stored for each of the letters, and aletter distance is generated according to the features of the letter foreach of the letters. Therefore, a storage capacity of the letterdistance data is considerably reduced even though a letter distancebetween letters adjacent to each other is changed for each of types ofthe letters. In detail, a region of a letter is divided into a pluralityof squared cells in a checker pattern, and particular squared cells inwhich portions of the letter exist are specified. Thereafter, a group ofparticular squared cells for a rear letter is connected to another groupof particular squared cells defined for another region of a fore letteradjacent to the rear letter on condition that the groups do not overlapeach other, so that a letter distance between the fore and rear lettersis determined for each of the combinations of the fore and rear letters.

2.2. Problems to be Solved by the Invention

However, because the letter distance is determined in a squared cellunit, a shortest distance between a portion of the fore letter and aportion of the rear letter is in a wide range from almost a zero to alength equal to a double cell width, so that there is a drawback thatthe letter distance considerably varies.

For example, the following describes an application of the letterdistance data generating apparatus to a letter string "TwA" according tothe kerning technique, with reference to FIGS. 1 to 8.

As shown in FIG. 1, a first region R1 of a first group of particularsquared cells for a letter "T", a second region R2 of a second group ofparticular squared cells for a letter "w" and a third region R3 of athird group of particular squared cells for a letter "A" are formed. Inthis case, because the letter "w" occupies only a small portion of aparticular squared cell C1 (hereinafter, "slightly occupies cell C1")and the letter "A" slightly occupies a particular squared cell C2connected to the cell C1, a shortest distance between the letter "w" andthe letter "A" is almost equal to a double cell width, as shown in FIG.2A. However, in cases where the letter "w" occupies a great part of theparticular squared cell C1 because of a positional relationship betweenthe letter "w" and the letter "T" and the second group of particularsquared cells for the letter "w" from the first, the shortest distancebetween the differently placed letter "w" and the letter "A" is almostas short as a single cell width, as shown in FIG. 2B. Therefore, incases where the letters "T", "w" and "A" of the letter string "TwA" areput close together in the letter distance data generating apparatus, thearrangement of the letters "T", "w" and "A" shown in FIG. 3A is obtainedin case of the positional relationship shown in FIG. 2A, and thearrangement of the letters "T","w" and "A" shown in FIG. 3B is obtainedin case of the positional relationship shown in FIG. 2B. As a result,the letter string "TwA" shown in FIG. 4A is printed or displayed in caseof the arrangement shown in FIG. 3A, and the letter string "TwA" shownin FIG. 4B is printed or displayed in case of the arrangement shown inFIG. 3B. In this case, a reader feels a letter distance between theletters "w" and "A" shown in FIG. 4A to be too long.

Also, as shown in FIG. 5, in cases where an upper left portion of theletter "w" slightly occupies a particular squared cell C3, a leftportion of the letter "w" is not placed under an upper right portion ofthe letter "T". Therefore, a letter distance between the letters "T" and"w" becomes too long.

Accordingly, there is a drawback in that a letter distance determined inthe letter distance data generating apparatus varies in dependence on apositional relationship between a letter and a group of squared cells,and letter distances in a letter string are not uniformly set.

Also, as shown in FIG. 6, in cases where the squared cells are downsizedto reduce the variation of a letter distance depending on the positionalrelationship, the letters "T","w" and "A" of the letter string "TwA" areput close together in the letter distance data generating apparatus asshown in FIG. 7. Therefore, the letter string "TwA" is printed ordisplayed. In this case, because a left portion of the letter "w" isexcessively placed under an upper right portion of the letter "T", areader feels uncomfortable to read the letter string "TwA".

Accordingly, there is a drawback in that that letter distances in aletter string vary in dependence on the size of the squared cells, andit is difficult to determine an appropriate size of squared cells forall alphanumeric characters.

Also, because the number of squared cells required for a letter isincreased in cases where the squared cells are downsized, a calculationvolume required to put letters of a letter string close together isextremely increased, so that there is another drawback in that that aprocessing speed for determining letter distances of the letters isdelayed.

In addition, in cases where a Japanese letter string "" of Japaneseletters "" and "" is printed or displayed, the Japanese letter stringshown in FIG. 9A is the best shape. However, in cases where the letterdistance data generating apparatus is applied for determining a letterdistance between the Japanese letters, the letters are put too closetogether when a size of squared cells is small, as shown in FIG. 9B.Also, even though large sized square cells are utilized in the letterdistance data generating apparatus to hopefully form the Japanese letterstring shown in FIG. 10A, the letters are still put too close together,and the Japanese letter string shown in FIG. 10B is undesirably printedor displayed.

Accordingly, there is a drawback in that the letter distance datagenerating apparatus (No. 361077 of 1992) cannot be applied for Japaneseletters or a Japanese letter string.

SUMMARY OF THE INVENTION

A first object of the present invention is to provide, with dueconsideration to the drawbacks of such a conventional letter distancedata generating apparatus, a character region determining apparatus andmethod in which a minimum character region required for a letter of analphanumeric character string or a Japanese letter string is easilydetermined by use of a small capacity sized memory.

A second object of the present invention is to provide a characterstring generating apparatus in which letters of a character string areput close together to arrange the letters at appropriate characterpitches on condition that the minimum character regions for the lettersdetermined in the minimum character region determining apparatusaccording to the minimum character region determining method are notoverlapped.

To achieve the first object, in the present invention, outline data of aletter placed in a rectangular character region is prepared. Thereafter,right proportional data indicating a right proportional position spacedapart from the letter toward a right direction is produced inproportional data producing means according to the outline data of theletter. Also, the rectangular character region of the letter ishorizontally partitioned into a plurality of partitive regions incharacter region partitioning means, so that the letter is horizontallypartitioned into a plurality of portions. Thereafter a right fitposition, at which a portion of the letter placed at the most right sidein one partitive region is positioned, is specified for each of thepartitive regions according to the outline data of the letter, and rightfit data indicating one right fit position is produced for each of thepartitive regions in a fit data producing means. Thereafter, in aminimum fit data determining means is determined right minimum fit data,denoting one right fit position placed on the most right side among theright fit positions of the right fit data. One partitive region relatingto the right minimum fit data is called a right minimum partitiveregion. Also, the right proportional data is set to right kerning datafor the right minimum partitive region in a first kerning data settingmeans. Thereafter, in a second kerning data setting means, a prescribedright value between a value of the right minimum fit data and a value ofone right fit data for one partitive region is set to a value of anotherright kerning data for each of the partitive regions other than theright minimum partitive region.

Therefore, the right kerning data for all partitive regions aredetermined. Also, in the same manner, left kerning data for allpartitive regions are determined from left minimum fit data for a leftminimum partitive region and left fit data. Thereafter, for a letterhaving a right side which is limited by a plurality of right kerningpositions indicated by the right kerning data and a left side which islimited by a plurality of left kerning positions indicated by the leftkerning data, a minimum character region is determined by a minimumcharacter region determining means, and the minimum character region isdisplayed.

Accordingly, because it is not required to store the kerning data forall types of letters in advance in a memory, and because the kerningdata for each letter are automatically calculated, a memory having alarge capacity is not required in order to determine the minimumcharacter region for each letter.

Also, because the minimum character region for each letter is specifiedby the kerning data, the letters of the word can be put close togetheron condition that the letters do not overlap each other.

To achieve the second object in the present invention, the letters arearranged in a line in the character arranging means, to put the lettersclose together on condition that the minimum character regionsdetermined for the letters in the minimum character region determiningmeans are not overlapped with each other, and a character stringcomposed of the letters is obtained. The character string is output bycharacter string outputting means.

Accordingly, when a plurality of letters, for which a plurality ofminimum character regions are determined, are arranged in series to forma word, because a space between each pair of adjacent letters can bearbitrarily adjusted by adjusting the proportional data, the prescribedright value between the right minimum fit data and one right fit datafor each partitive region, and the prescribed left value between theleft minimum fit data and one left fit data for each partitive region, aperson can feel that letter spaces in the word are uniformly set, andthe letter spaces in the word can be rapidly determined.

BRIEF DESCRIPTION OF THE DRAWINGS

The objects, features and advantages of the present invention will beapparent from the following description taken in conjunction with theaccompanying drawings, in which:

FIG. 1 shows a letter string "TwA" arranged in a plurality of squaredcells;

FIG. 2A shows a shortest letter distance between letters "w" and "A"shown in FIG. 1;

FIG. 2B shows another shortest letter distance between letters "w" and"A" arranged according to another case;

FIG. 3A shows the arrangement of the letters "T", "w" and "A" shown inFIG. 2A according to letter distances determined in a conventionalletter distance data generating apparatus;

FIG. 3B shows the arrangement of the letters "T", "w" and "A" shown inFIG. 2B according to letter distances determined in the conventionalletter distance data generating apparatus;

FIG. 4A shows a letter string "TwA" of the letters "T", "w" and "A"shown in FIG. 3A;

FIG. 4B shows a letter string "TwA" of the letters "T", "w" and "A"shown in FIG. 3B;

FIG. 5 shows a letter string "TwA" in which an upper left portion of theletter "w" slightly occupies a particular squared cell C3;

FIG. 6 shows a letter string "TwA" placed in downsized square cells;

FIG. 7 shows the arrangement of the letter string "TwA" placed indownsized square cells in which the letters "T", "w" and "A" are putclose together in the conventional letter distance data generatingapparatus;

FIG. 8 shows the letter string "TwA" shown in FIG. 7 which is printed ordisplayed;

FIG. 9A shows a Japanese letter string in the best arrangement;

FIG. 9B shows the Japanese letter string, which is placed in small sizedsquare cells, shaped in the conventional letter distance data generatingapparatus;

FIG. 10A shows a Japanese letter string with enlarged square cells inthe best arrangement;

FIG. 10B shows the Japanese letter string, which is placed in enlargedsquare cells, shaped in the conventional letter distance data generatingapparatus;

FIG. 11 is a block diagram of a character pitch determining apparatusaccording to an embodiment of the present invention;

FIG. 12 is a flow chart of a minimum character region determining methodperformed in the minimum character region determining apparatus shown inFIG. 11;

FIGS. 13A to 13F show a procedure of the minimum character regiondetermining method in which a minimum character region for a letter "A"is determined;

FIG. 14 is a graphic view for explaining an intersection pointcalculating method applied for a segment line crossing both a top-middleboundary line Ltm and a middle-bottom boundary line Lmb;

FIG. 15 shows a minimum character region for a letter "F" determinedaccording to the minimum character region determining method;

FIG. 16 shows a minimum character region for a letter "0" determinedaccording to the minimum character region determining method;

FIG. 17 shows a minimum character region for a letter "T" determinedaccording to another minimum character region determining method appliedin cases where a maximum difference among right fit distances Df1,Df2and Df3 or left fit distances Df4,Df5 and Df6 is higher than aprescribed value;

FIG. 18 is a block diagram of a character pitch determining apparatusaccording to another embodiment of the present invention;

FIG. 19 is a block diagram of a character string generating apparatusaccording to an embodiment of the present invention;

FIG. 20 shows a character string "AV" having letters "A" and "V" ofwhich minimum character regions are determined according to the minimumcharacter region determining method shown in FIGS. 12 and 13, theletters "A" and "V" being put close together in the character stringgenerating apparatus shown in FIG. 19;

FIG. 21 shows a method for arranging the letters "A" and "V" in acharacter arranging unit of the character string generating apparatusshown in FIG. 19;

FIG. 22A shows Japanese letters "" and "" of which squared characterregions are connected to each other;

FIG. 22B shows a Japanese letter string arranged in the character stringgenerating apparatus shown in FIG. 19;

FIG. 23 is a block diagram of a character string generating apparatusaccording to another embodiment of the present invention; and

FIG. 24 is a block diagram of a character string generating apparatusaccording to another embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of a character pitch determining apparatus andmethod according to the present invention are described with referenceto drawings.

FIG. 11 is a block diagram of a character pitch determining apparatusaccording to an embodiment of the present invention.

As shown in FIG. 11, a minimum character region determining apparatus 11comprises an outline data storing unit 12 formed of a read only memory(ROM) for storing pieces of outline data for each of letters such asalphanumeric characters and Japanese letters, a proportional dataproducing unit 13 for selecting pieces of outline data for a letterstored in the storing unit 12 and producing a piece of rightproportional data and a piece of left proportional data for the letteraccording to the outline data, a character region partitioning unit 14for equally partitioning a squared character region of the letterselected in the producing unit 13 into a top partitive region, a middlepartitive region and a bottom partitive region arranged in alongitudinal direction (or a Y-axis direction) in that order topartition the outline data for the letter, a fit data calculating unit15 for calculating six pieces of fit data such as a piece of top-rightfit data denoting a lateral (or X-axis) directional position of aportion of the letter placed at the most right side in the top partitiveregion produced in the partitioning unit 14, a piece of top-left fitdata denoting another lateral directional position of a portion of theletter placed at the most left side in the top partitive region, a pieceof middle-right fit data denoting a lateral directional position of aportion of the letter placed at the most right side in the middlepartitive region produced in the partitioning unit 14, a piece ofmiddle-left fit data denoting another lateral directional position of aportion of the letter placed at the most left side in the middlepartitive region, a piece of bottom-right fit data denoting a lateraldirectional position of a portion of the letter placed at the most rightside in the bottom partitive region produced in the partitioning unit 14and a piece of bottom-left fit data denoting another lateral directionalposition of a portion of the letter placed at the most left side in thebottom partitive region, a minimum fit data determining unit 16 fordetermining a piece of fit data placed at the most right side among thetop-right fit data, the middle-right fit data and the bottom-right fitdata calculated in the calculating unit 15 as a piece of right minimumfit data and determining a piece of fit data placed at the most leftside among the top-left fit data, the middle-left fit data and thebottom-left fit data calculated in the calculating unit 15 as a piece ofleft minimum fit data, a kerning data calculating unit 17 forcalculating a top-right kerning data of the top portion of the letterdenoting a lateral directional position in the top partitive region byutilizing the right proportional data generated in the producing unit 13or the combination of the top-right fit data calculated in thecalculating unit 15 and the minimum right fit data determined in thedetermining unit 16, calculating a middle-right kerning data of themiddle portion of the letter denoting a lateral directional position inthe middle partitive region by utilizing the right proportional data orthe combination of the middle-right fit data calculated in thecalculating unit 15 and the minimum right fit data, calculating abottom-right kerning data of the bottom portion of the letter denoting alateral directional position in the bottom partitive region by utilizingthe right proportional data or the combination of the bottom-right fitdata calculated in the calculating unit 15 and the minimum right fitdata, calculating a top-left kerning data of the top portion of theletter denoting a lateral directional position in the top partitiveregion by utilizing the left proportional data or the combination of thetop-left fit data calculated in the calculating unit 15 and the minimumleft fit data determined in the determining unit 16, calculating amiddle-left kerning data of the middle portion of the letter denoting alateral directional position in the middle partitive region by utilizingthe left proportional data or the combination of the middle-left fitdata calculated in the calculating unit 15 and the minimum left fitdata, and calculating a bottom-left kerning data of the bottom portionof the letter denoting a lateral directional position in the bottompartitive region by utilizing the left proportional data or thecombination of the bottom-left fit data calculated in the calculatingunit 15 and the minimum left fit data, and a minimum character regiondetermining unit 18 for determining a minimum character region for theletter of which a right side is limited by the lateral directionalpositions denoted by the top-right kerning data, the middle-rightkerning data and the bottom-right kerning data and a left side islimited by the lateral directional positions denoted by the top-leftkerning data, the middle-left kerning data and the bottom-left kerningdata.

In the above configuration, a character pitch determining method isbriefly described with reference to FIG. 12.

FIG. 12 is a flow chart of a minimum character region determining methodperformed in the minimum character region determining apparatus 11 shownin FIG. 11.

As shown in FIG. 12, a letter such as an alphanumeric character or aJapanese letter of a character string is specified, and pieces ofoutline data for the letter are read out from the outline data storingunit 12 in a step S111. Thereafter, a piece of right proportional dataand a piece of left proportional data for the letter are produced fromthe outline data in the proportional data producing unit 13 in a stepS112. Thereafter, a squared character region of the letter is equallypartitioned into a top partitive region, a middle partitive region and abottom partitive region arranged in a longitudinal direction (or aY-axis direction) in that order in the character region partitioningunit 14 in a step S113. Thereafter, six pieces of fit data such as apiece of top-right fit data, a piece of top-left fit data, a piece ofmiddle-right fit data, a piece of middle-left fit data, a piece ofbottom-right fit data and a piece of bottom-left fit data are calculatedin the fit data calculating unit 15 in a step S114.

Thereafter, a piece of right minimum fit data and a piece of leftminimum fit data are determined in the minimum fit data determining unit16 in a step S115. That is, a piece of fit data placed at the most rightside among the top-right fit data, the middle-right fit data and thebottom-right fit data is selected and is regarded as the right minimumfit data. Also, a piece of fit data placed at the most left side amongthe top-left fit data, the middle-left fit data and the bottom-left fitdata is selected and is regarded as the left minimum fit data.

Thereafter, six pieces of kerning data are calculated in the kerningdata calculating unit 17 in a step S116. That is, a top-right kerningdata of the top portion of the letter denoting a lateral directionalposition in the top partitive region is calculated by utilizing theright proportional data or the combination of the top-right fit data andthe minimum right fit data, a middle-right kerning data of the middleportion of the letter denoting a lateral directional position in themiddle partitive region is calculated by utilizing the rightproportional data or the combination of the middle-right fit data andthe minimum right fit data, and a bottom-right kerning data of thebottom portion of the letter denoting a lateral directional position inthe bottom partitive region is calculated by utilizing the rightproportional data or the combination of the bottom-right fit data andthe minimum right fit data. Also, a top-left kerning data of the topportion of the letter denoting a lateral directional position in the toppartitive region is calculated by utilizing the left proportional dataor the combination of the top-left fit data and the minimum left fitdata, a middle-left kerning data of the middle portion of the letterdenoting a lateral directional position in the middle partitive regionis calculated by utilizing the left proportional data or the combinationof the middle-left fit data and the minimum left fit data, and abottom-left kerning data of the bottom portion of the letter denoting alateral directional position in the bottom partitive region iscalculated by utilizing the left proportional data or the combination ofthe bottom-left fit data and the minimum left fit data.

Thereafter, a minimum character region enclosed by the top-right kerningdata, the middle-right kerning data, the bottom-right kerning data, thetop-left kerning data, the middle-left kerning data and the bottom-leftkerning data is produced in the minimum character region producing unit18 in a step S117.

Therefore, a minimum character region required for a letter isdetermined according to the minimum character region determining methodshown in FIG. 12 in the minimum character region determining apparatus11. In cases where letters of a character string are put close togetheron condition that the minimum character regions for the letters are notoverlapped, the letters are arranged to provide a comfortable feelingfor a reader.

Thereafter, it is judged in a step S118 whether or not the kerning datafor all of letters in the character string are calculated in the stepsS111 to S117. In cases where the kerning data for all of the letters inthe character string are not calculated, the procedure returns to thestep S111 to calculate six pieces of kerning data for another letter inthe steps S111 to S117. In contrast, in cases where the kerning data forall of the letters in the character string are calculated, the lettersin the character string are put close together on condition that theenclosed regions for the letters are not overlapped in a step S119.Thereafter, the character string is displayed on a display or is printedout on a printing paper in a step S120.

Next, the operation of the minimum character region determiningapparatus 11 according to the minimum character region determiningmethod is described in detail.

After a letter of a character string is specified, pieces of outlinedata of the letter are read out from the outline data storing unit 12.As shown in FIG. 13A, the outline data of the letter is defined in asquared character region Rc so as to reproduce the letter "A". That is,an outline of the letter is approximately expressed by a plurality ofline segments, and the outline data indicate starting and endingpositions of each of the line segments. Thereafter, a piece of rightproportional data and a piece of left proportional data of the letterare produced from the outline data in the proportional data producingunit 13. As shown in FIG. 13B, the right proportional data denotes aright proportional distance Dp1 between a right proportional line Lp1and a right side line Ls1 of the squared character region Rc, and theleft proportional data denotes a left proportional distance Dp2 betweena left proportional line Lp2 and a left side line Ls2 of the squaredcharacter region Rc.

Thereafter, the squared character region Rc of the letter is equallypartitioned into a top partitive region Rt, a middle partitive region Rmand a bottom partitive region Rb arranged in a longitudinal direction inthat order in the character region partitioning unit 14. In this case,an upper side line Ls3 of the squared character region Rc is defined bya Y coordinate Y=0, a lower side line Ls4 of the squared characterregion Rc is defined by a Y coordinate Y=511, a top-middle boundary lineLtm between the top partitive region Rt and the middle partitive regionRm is defined by a Y coordinate Y=151, and a middle-bottom boundary lineLmb between the middle partitive region Rm and the bottom partitiveregion Rb is defined by a Y coordinate Y=342.

Thereafter, six pieces of fit data such as a piece of top-right fitdata, a piece of top-left fit data, a piece of middle-right fit data, apiece of middle-left fit data, a piece of bottom-right fit data and apiece of bottom-left fit data are calculated in the fit data calculatingunit 15. In detail, as shown in FIG. 13D, the top-right fit data denotesa lateral directional position of a portion of the letter placed at themost right side in the top partitive region Rt, and the position isdefined as a top-right fit distance Df1 between a top-right fit line Lf1indicating the portion of the letter placed at the most right side andthe right side line Ls1. The middle-right fit data denotes a lateraldirectional position of a portion of the letter placed at the most rightside in the middle partitive region Rm, and the position is defined as amiddle-right fit distance Df2 between a middle-right fit line Lf2indicating the portion of the letter placed at the most right side andthe right side line Ls1. The bottom-right fit data denotes a lateraldirectional position of a portion of the letter placed at the most rightside in the bottom partitive region Rb, and the position is defined as abottom-right fit distance Df3 between a bottom-right fit line Lf3indicating the portion of the letter placed at the most right side andthe right side line Ls1. The top-left fit data denotes a lateraldirectional position of a portion of the letter placed at the most leftside in the top partitive region Rt, and the position is defined as atop-left fit distance Df4 between a top-left fit line Lf4 indicating theportion of the letter placed at the most left side and the left sideline Ls2. The middle-left fit data denotes a lateral directionalposition of a portion of the letter placed at the most left side in themiddle partitive region Rm, and the position is defined as a middle-leftfit distance Df5 between a middle-left fit line Lf5 indicating theportion of the letter placed at the most left side and the left sideline Ls2. The bottom-left fit data denotes a lateral directionalposition of a portion of the letter placed at the most left side in thebottom partitive region Rb, and the position is defined as a bottom-leftfit distance Df6 between a bottom-left fit line Lf6 indicating theportion of the letter placed at the most left side and the left sideline Ls2.

Therefore, because a position of the letter in the square characterregion Rc is specified by the right fit lines Lf1,Lf2 and Lf3 and theleft fit lines Lf4, Lf5 and Lf6 defined for all of the partitive regionsRt,Rm and Rb, shape features of the letter are specified by the rightfit data and the left fit data for each of the partitive regions Rt,Rmand Rb.

In this case, because the outline data indicate the starting and endingpositions of each of the line segments, pieces of positional data of theletter at the top-middle boundary line Ltm and the middle-bottomboundary line Lmb are not explicitly provided in cases where thestarting or ending position is not placed at the top-middle boundaryline Ltm and the middle-bottom boundary line Lmb. Therefore, in caseswhere a line segment of the letter crosses the top-middle boundary lineLtm or the middle-bottom boundary line Lmb, it is required to judgewhich is placed closely to the right or left side line Ls1 or Ls2, aposition of the line segment at the top-middle (or the middle-bottom)boundary line Ltm (or Lmb) or a starting (or ending) position of a linesegment. In this embodiment, a position of the line segment at thetop-middle or middle-bottom boundary line Ltm or Lmb is determinedaccording to an intersection point calculating method, and it is judgedwhich represents a lateral directional position of a piece of fit data,the position of the line segment calculated according to theintersection point calculating method or a starting (or ending) positionof a line segment placed at the most right (or left) side among allstarting and ending positions of line segments in the partitive regionRt, Rm or Rb.

The intersection point calculating method applied for a segment linecrossing both the top-middle boundary line Ltm and the middle-bottomboundary line Lmb is described in detail as an example with reference toFIG. 14. In cases where starting and ending points Ps and Pe of asegment line L1 are expressed by starting coordinates (x1,y1) and endingcoordinates (x2,y2), a line including the segment line L1 is expressedaccording to an equation (1) in an X-Y coordinate system.

    Y=(y1-y2)/(x1-x2)*X+C1                                     (1)

A constant C1 is obtained by substituting (x1,y1) into (X,Y) accordingto an equation (2).

    C1=(x1*y2-x2*y1)/(x1-x2)                                   (2)

Therefore, the equation (1) can be rewritten to an equation (3) bysubstituting the equation (2) into the equation (1).

    Y32 {(y1-y2)*X+(x1*y2-x2*y1)}/(x1-x2)                      (3)

Because a Y coordinate of a first intersection P1 between the linesegment L1 and the top-middle boundary line Ltm is Y=342, an Xcoordinate x3 of the first intersection P1 is obtained according to anequation (4).

    x3={342*(x1-x2)-(x1*y2-x2*y1)}/(y1-y2)                     (4)

Also, a Y coordinate of a second intersection P2 between the linesegment L1 and the middle-bottom boundary line Lmb is Y=151, an Xcoordinate x4 of the second intersection P2 is obtained according to anequation (5).

    x3 ={151*(x1=x2)-(x1*y2-x2*y1)}/(y1-y2)                    (5)

In cases where a segment line crosses only the top-middle boundary lineLtm, an X coordinate of an intersection point can be obtained accordingto the equation (4). Also, in cases where a segment line crosses onlythe middle-bottom boundary line Lmb, an X coordinate of an intersectionpoint can be obtained according to the equation (5).

Assuming that a minimum character region required by a letter is anenclosed region specified by the six fit data, there is a probabilitythat a character pitch between letters becomes zero when letters of acharacter string put close together. For example, in cases where a foreletter "H" and a rear letter "E" is adjacent to each other in thatorder, the letters "H" and "E" are attached each other without anycharacter pitch. Therefore, a minimum character region required by aletter is produced to be wider that that specified by the six fit data.

That is, a piece of fit data placed at the most right side among thetop-right fit data, the middle-right fit data and the bottom-right fitdata is selected and is treated as a piece of right minimum fit data inthe minimum fit data determining unit 16. Also, a piece of fit dataplaced at the most left side among the top-left fit data, themiddle-left fit data and the bottom-left fit data is selected and istreated as a piece of left minimum fit data in the minimum fit datadetermining unit 16. As shown in FIG. 13D, in cases where the letter "A"is specified to determine a minimum character region of the letter "A",the bottom-right fit data is regarded as the right minimum fit data, andthe bottom-left fit data is regarded as the left minimum fit data.

Thereafter, six pieces of kerning data such as a piece of top-rightkerning data, a piece of middle-right kerning data, a piece ofbottom-right kerning data, a piece of top-left kerning data, a piece ofmiddle-left kerning data and a piece of bottom-left kerning data arecalculated in the kerning data calculating unit 17. In detail, the rightproportional data is set as a piece of right kerning data denoting alateral directional position in a partitive region Rt,Rm or Rb in whichthe right minimum fit data is defined, and the left proportional data isset as a piece of left kerning data denoting a lateral directionalposition in a partitive region Rt,Rm or Rb in which the left minimum fitdata is defined. As shown in FIG. 13E, in cases where the letter "A" isspecified to determine a minimum character region of the letter "A", theright proportional data is set as a piece of bottom-right kerning databecause the bottom-right fit data is regarded as the right minimum fitdata, and the left proportional data is set as a piece of bottom-leftkerning data because the bottom-left fit data is regarded as the leftminimum fit data. The bottom-right kerning data denotes the rightproportional distance Dp1 between a right minimum fit line Lf7 and theright side line Ls1, and the bottom-left kerning data denotes the leftproportional distance Dp2 between a left minimum fit line Lf8 and theleft side line Ls2.

Each of other pieces of right kerning data is calculated to set alateral directional position designated by each of the other rightkerning data to a middle position between a right fit line Lf1,Lf2 orLf3 of a piece of corresponding fit data and a lateral directionalposition denoted by the minimum right fit data. That is, in cases wherethe bottom-right fit data is regarded as the right minimum fit data, atop-right kerning distance Dk1 between the the right side line Ls1 and atop-right kerning line Lk1 designated by the top-right kerning data isdetermined as the top-right kerning data according to an equation (6),and a middle-right kerning distance Dk2 between the right side line Ls1and a middle-right kerning line Lk2 designated by the middle-rightkerning data is determined as the middle-right kerning data according toan equation (7). ##EQU1## In this case, a bottom-right kerning distanceDk3 is set to the value Dp1 as the bottom-right kerning data.

Also, in cases where the bottom-left fit data is regarded as the leftminimum fit data, a top-left kerning distance Dk4 between the left sideline Ls2 and a top-left kerning line Lk4 designated by the top-leftkerning data is determined as the top-left kerning data according to anequation (8), and a middle-left kerning distance Dk5 between the leftside line Ls2 and a middle-left kerning line Lk5 designated by themiddle-left kerning data is determined as the middle-left kerning dataaccording to an equation (9). ##EQU2## In this case, a bottom-leftkerning distance Dk6 is set to the value Dp2 as the bottom-left kerningdata.

In cases where the top-right fit data is regarded as the right minimumfit data, a middle-right kerning distance Dk2 between the right sideline Ls1 and a middle-right kerning line Lk2 designated by themiddle-right kerning data is determined as the middle-right kerning dataaccording to an equation (10), and a bottom-right kerning distance Dk3between the right side line Ls1 and a bottom-right kerning line Lk3designated by the bottom-right kerning data is determined as thebottom-right kerning data according to an equation (11). ##EQU3## Inthis case, a top-right kerning distance Dk1 is set to the value Dp1 asthe top-right kerning data.

Also, in cases where the top-left fit data is regarded as the leftminimum fit data, a middle-left kerning distance Dk5 between the leftside line Ls2 and a middle-left kerning line Lk5 designated by themiddle-left kerning data is determined as the middle-left kerning dataaccording to an equation (12), and a bottom-left kerning distance Dk6between the left side line Ls2 and a bottom-left kerning line Lk6designated by the bottom-left kerning data is determined as thebottom-left kerning data according to an equation (13). ##EQU4## In thiscase, a top-left kerning distance Dk4 is set to the value Dp2 as thetop-left kerning data.

In cases where the middle-right fit data is regarded as the rightminimum fit data, a top-right kerning distance Dk1 between the the rightside line Ls1 and a top-right kerning line Lk1 designated by thetop-right kerning data is determined as the top-right kerning dataaccording to an equation (14), and a bottom-right kerning distance Dk3between the right side line Ls1 and a bottom-right kerning line Lk3designated by the bottom-right kerning data is determined as thebottom-right kerning data according to an equation (15). ##EQU5## Inthis case, a middle-right kerning distance Dk2 is set to the value Dp1as the middle-right kerning data.

Also, in cases where the middle-left fit data is regarded as the leftminimum fit data, a top-left kerning distance Dk4 between the left sideline Ls2 and a top-left kerning line Lk4 designated by the top-leftkerning data is determined as the top-left kerning data according to anequation (16), and a bottom-left kerning distance Dk6 between the leftside line Ls2 and a bottom-left kerning line Lk6 designated by thebottom-left kerning data is determined as the bottom-left kerning dataaccording to an equation (17). ##EQU6## In this case, a middle-leftkerning distance Dk5 is set to the value Dp2 as the middle-left kerningdata.

As shown in FIG. 13F, in cases where the letter "A" is specified todetermine a minimum character region for the letter "A", a minimumcharacter region R0 required by the letter "A" is determined in the unit18 by the top-right kerning line Lk1 designated by the top-right kerningdata, the middle-right kerning line Lk2 designated by the middle-rightkerning data, the right minimum fit line Lf7 designated by the rightminimum fit data, the top-left kerning line Lk4 designated by thetop-left kerning data, the middle-left kerning line Lk5 designated bythe middle-left kerning data and the left minimum fit line Lf8designated by the left minimum fit data. The minimum character region R0is composed of a top partitive character region Rct placed on the toppartitive region Rt, a middle partitive character region Rcm placed onthe middle partitive region Rm and a bottom partitive character regionRcb placed on the bottom partitive region Rb.

Also, in cases where a minimum character region R0 required by a lettersuch as "F" is calculated, the top-right fit data is regarded as theright minimum fit data, and the top-left fit data is regarded as theleft minimum fit data. Therefore, as shown in FIG. 15, an enclosedregion of the letter "F" is determined by the right minimum fit lineLf7, the middle-right kerning line Lk2 designated by the middlerightkerning data, the bottom-right kerning line Lk3 designated by thebottom-right kerning data, the left minimum fit line Lf8, themiddle-left kerning line Lk5 designated by the middle-left kerning dataand the bottom-left kerning line Lk6 designated by the top-left kerningdata as a minimum character region R0 required for the letter "F".

Also, in cases where a minimum character region R0 required by a lettersuch as "O" is calculated, the middle-right fit data is regarded as theright minimum fit data, and the middle-left fit data is regarded as theleft minimum fit data. Therefore, as shown in FIG. 16, an enclosedregion of the letter "O" is determined by the top-right kerning line Lk1designated by the top-right kerning data, the right minimum fit lineLf7, the bottom-right kerning line Lk3 designated by the bottom-rightkerning data, the top-left kerning line Lk4 designated by the top-leftkerning data, the left minimum fit line Lf8 and the bottom-left kerningline Lk6 designated by the top-left kerning data as a minimum characterregion R0 required for the letter "O".

Accordingly, because a minimum character region R0 required for a letteris specified by the kerning data regardless of a first adjacent wordpreceding to the word and a second adjacent word succeeding to the word,a storage capacity required to store the kerning data produced for allof letters can be considerably reduced. Therefore, letters in acharacter string are put close together by utilizing a standard-gradecomputer having a small capacity type memory on condition that theminimum character regions for the letters are not overlapped each other.

Also, because sizes of the partitive character regions Rct, Rcm and Rcbof the minimum character region R0 for a letter are respectivelydetermined according to the right and left kerning data produced fromthe right and left fit data which specify shape features of the letter,it is substantially judged whether a side portion of the letter isparallel to the Y-axis, is inclined to the Y-axis, or is vertical to theY-axis. Therefore, in cases where letters of a character string are putclose together on condition that the minimum character regions R0 forthe letters are not overlapped each other, the letters of the characterstring can be arranged for a reader to feel comfortable becausecharacter pitches between the letters are determined by consideringshape features of each of the letters.

In the above embodiment, a coefficient of 0.5 is utilized in theequations (6) to (17). However, in cases where a fit data differencebetween the right minimum fit data and a piece of fit data placed at themost left side among the top-right fit data, the middle-right fit dataand the bottom-right fit data is more than a prescribed value, it ispreferred that the coefficient utilized for the right kerning distancesDk1,Dk2 and Dk3 be set to 0.6 to enlarge the minimum character region R0for a letter determined in the minimum character region determiningapparatus 11. In the same manner, in cases where a fit data differencebetween the left minimum fit data and a piece of fit data placed at themost right side among the top-left fit data, the middle-left fit dataand the bottom-left fit data is more than a prescribed value, it ispreferred that the coefficient utilized for the left kerning distancesDk4,Dk5 and Dk6 be set to 0.6 to enlarge the minimum character region R0for a letter determined in the minimum character region determiningapparatus 11. For example, as shown in FIG. 17, a minimum characterregion R0 for a letter "T" in a character string "TwA" is determined inthe apparatus 11, a middle-right kerning distance D'k2 and abottom-right kerning distance D'k3 are determined according to equations(18), (19) because the top-right fit distance Df1 has a minimum valueamong the fit distances Df1,Df2 and Df3.

    D'k2=Df2-(Df2-Df1)*0.6                                     (18)

    D'k3=Df3-(Df3-Df1)*0.6                                     (19)

Therefore, because the distances D'k2, D'k3 are shorter than thedistances Dk2, Dk3, a character pitch between the letter "T" and theletter "w" can be put close together so as to prevent that the letter"w" excessively approaches the letter "T".

Accordingly, the character string "TwA" looks to arrange the letters"T","w" and "A" more uniformly.

Also, in cases where it is desired to print or display a characterstring in which letters are put close together more uniformly andreadably, it is preferred that a minimum character region R0 for each ofletters in the character string be shrunk. For example, in cases wherethe bottom-right fit data is regarded as the right minimum fit data, atop-right kerning distance D"k1 and a middle-right kerning distance D"k2are determined according to equations (20), (21).

    D"k1=Df1-(Df1-Df3)*0.5-(Df3-Dp1)                           (20)

    D"k2=Df2-(Df2-Df3)*0.5-(Df3-Dp1)                           (21)

In this case, a bottom-right kerning distance D"k3 is set to the valueDk1. Also, in cases where the bottom-left fit data is regarded as theleft minimum fit data, a top-left kerning distance D"k4 and amiddle-left kerning distance D"k5 are determined according to equations(22), (23).

    D"k4=Df4-(Df4-Df6)*0.5-(Df6-Dp2)                           (22)

    D"k5=Df5-(Df5-Df6)*0.5-(Df6-Dp2)                           (23)

In this case, a bottom-left kerning distance D"k6 is set to the valueDk6. Also, in cases where the top-right fit data is regarded as theright minimum fit data, a middle-right kerning distance D"k2 and abottom-right kerning distance D"k3 are determined according to equations(24), (25).

    D"k2=Df2-(Df2-Df1)*0.5-(Df1-Dp1)                           (24)

    D"k3=Df3-(Df3-Df1)*0.5-(Df1-Dp1)                           (25)

In this case, a top-right kerning distance D"k1 is set to the value Dk1.Also, in cases where the top-left fit data is regarded as the leftminimum fit data, a middle-left kerning distance D"k5 and a bottom-leftkerning distance D"k6 are determined according to equations (26), (27).

    D"k5=Df5-(Df5-Df4)*0.5-(Df4-Dp2)                           (26)

    D"k6=Df6-(Df6-Df4)*0.5-(Df4-Dp2)                           (27)

In this case, a top-left kerning distance D"k4 is set to the value Dk4.Also, in cases where the middle-right fit data is regarded as the rightminimum fit data, a top-right kerning distance D"k1 and a bottom-rightkerning distance D"k3 are determined according to equations (28), (29).

    D"k1=Df1-(Df1-Df2)*0.5-(Df2-Dp1)                           (28)

    D"k3=Df3-(Df3-Df2)*0.5-(Df2-Dp1)                           (29)

In this case, a middle-right kerning distance D"k2 is set to the valueDk2. Also, in cases where the middle-left fit data is regarded as theleft minimum fit data, a top-left kerning distance D"k4 and abottom-left kerning distance D"k6 are determined according to equations(30), (31).

    D"k4=Df4-(Df4-Df5)*0.5-(Df5-Dp2)                           (30)

    D"k6=Df6-(Df6-Df5)*0.5-(Df5-Dp2)                           (31)

In this case, a middle-left kerning distance D"k5 is set to the valueDk5.

Accordingly, because values of third terms in the equations (20) to (31)determined according to a shape of each of letters in a characterstring, in cases where a plurality of minimum character regions forletters specified by the kerning distances D"k1 to D"6 are connected inseries to each other on condition that the minimum character regions arenot overlapped each other, letters of a character string can be moreuniformly put close together, and a reader feels more readably to readthe character string.

Also, the minimum character region determining apparatus 11 shown inFIG. 11 is utilized in the above embodiment.

However, as shown in FIG. 18, it is applicable that a minimum characterregion determining apparatus 21 comprise an outline data andproportional data storing unit 22, the partitioning unit 14, thecalculating unit 15, the determining unit 16, the calculating unit 17and the minimum character region determining unit 18. That is, pieces ofoutline data for each of letters such as alphanumeric characters andJapanese letters, a piece of right proportional data for each of theletters and a piece of left proportional data for each of the lettersare stored in the outline data and proportional data storing unit 22.Therefore, a set of pieces of outline data, a piece of rightproportional data and a piece of left proportional data is read out tothe partitioning unit 14, the calculating unit 15, the determining unit16 and the calculating unit 17 for each of the letters.

Accordingly, because a piece of right proportional data or each of theletters and a piece of left proportional data for each of the lettersare stored in advance in the storing unit 22, the producing unit 13 isnot required, so that the configuration of the minimum character regiondetermining apparatus 21 can be simplified.

Also, because the calculation of the right and left proportional datafor each of the letters can be omitted, a minimum character region R0for each of the letter can be quickly determined in the minimumcharacter region determining apparatus 21.

In addition, a storage capacity required to store the right and leftproportional data for the letters is not so much. Therefore, not onlyminimum character regions of the alphanumeric letters but also minimumcharacter regions of Japanese letters, Japanese secondary letters called"katakana" in Japan and Chinese characters used in Japanese writing canbe determined according to the minimum character region determiningmethod in the minimum character determining apparatus 11.

Next, a character string generating apparatus according to an embodimentof the present invention is described.

FIG. 19 is a block diagram of a character string generating apparatus,which is connected to the minimum character region determining apparatus11 shown in FIG. 11, according to an embodiment of the presentinvention.

As shown in FIG. 19, a character string generating apparatus 31comprises a character arranging unit 32 for arranging letters of acharacter string according to the the minimum character regions for theletters obtained in the minimum character region determining unit 18 ofthe minimum character region determining apparatus 11 to put the lettersclose together, and a character string outputting unit 33 for displayingor printing the character string, of which the letters are put closetogether in the arranging unit 32, on a display or on a printing paper.

In the above configuration, a fore letter and a rear letter adjacent toeach other in a character string approach together in the arranging unit32 to connect at least one of partitive character regions Rct, Rcm andRcb of a minimum character region R0 for the fore letter to acorresponding partitive character region Rct, Rcm or Rcb of anotherminimum character region R0 for the rear letter on condition that theminimum character regions are not overlapped. For example, as shown inFIG. 20, in cases where a fore letter "A" and a rear letter "V" areexpected to be put close together in the arranging unit 32, a middlepartitive character region Rcm of a minimum character region R0 for thefore letter "A" is connected to a middle partitive character region Rcmof a minimum character region R0 for the rear letter "V". In this case,top partitive character regions Rct facing each other are not connected,and bottom partitive character regions Rcb facing each other are notconnected.

In this embodiment, a pair of minimum character regions for fore andrear letters is connected together as follows to put the fore and rearletters close together.

As shown in FIG. 21, squared character regions of fore and rear lettersare arranged to be adjacent to each other. Thereafter, a top-rightkerning distance Dk1 for the fore letter and a top-left kerning distanceDk4 for the rear letter are added to obtain a top summed value, amiddle-right kerning distance Dk2 for the fore letter and a middle-leftkerning distance Dk5 for the rear letter are added to obtain a middlesummed value, and a bottom-right kerning distance Dk3 for the foreletter and a bottom-left kerning distance Dk6 for the rear letter areadded to obtain a bottom summed value. Thereafter, a minimum value amongthe top summed value, the middle summed value and the bottom summedvalue is selected. Thereafter, the minimum value is subtracted from thetop summed value to obtain a top subtracted value, the minimum value issubtracted from the middle summed value to obtain a middle subtractedvalue, and the minimum value is subtracted from the bottom summed valueto obtain a bottom subtracted value. Thereafter, top partitive characterregions Rct of minimum character regions R0 for the fore and rearletters are arranged to set a top distance between the top partitivecharacter regions Rct to the top subtracted value, middle partitivecharacter regions Rcm of the minimum character regions R0 are arrangedto set a middle distance between the middle partitive character regionsRcm to the middle subtracted value, and bottom partitive characterregions Rcb of the minimum character regions R0 are arranged to set abottom distance between the bottom partitive character regions Rcb tothe bottom subtracted value. Therefore, as shown in FIG. 20, the foreand rear letters can be put close together for a reader to feelcomfortable.

Accordingly, because sizes of the partitive character regions Rct, Rcmand Rcb of the minimum character region R0 for each of letters in acharacter string are respectively determined in the minimum characterregion determining apparatus 11, it is substantially judged whether aside portion of a letter is parallel to the Y-axis, is inclined to theY-axis, or is vertical to the Y-axis. Therefore, letters in a characterstring can be put close together while substantially considering shapesof the letters. In other words, letters in a character string can be putclose together according to shapes of the letters. As a result, a readercan feels that letters of a character string are spaced at equaldistances, so that the reader can feel comfortable.

Also, in cases where the character string generating apparatus 31 isutilized to put Japanese letters of a Japanese letter string "" closetogether, the Japanese letter string in which squared character regionsof the Japanese letters are connected each other as shown in FIG. 22A isdisplayed or printed as shown in FIG. 22B. Therefore, the Japaneseletters are not excessively put close together.

Accordingly, the minimum character region determining apparatus 11 andthe character string generating apparatus 31 can be useful for theJapanese letter string.

In the above embodiment of the character string generating apparatus,the character string generating apparatus 31 is connected to the minimumcharacter region generating apparatus 11. However, as shown in FIG. 23,it is applicable that a character string generating apparatus 41comprise an outline data and kerning data storing unit 42, the characterarranging unit 32 and the character string outputting unit 33. That is,pieces of outline data, a piece of top-right kerning data, a piece ofmiddle-right kerning data, a piece of bottom-right kerning data, a pieceof top-left kerning data, a piece of middle-left kerning data and apiece of bottom-left kerning data for each of letters such asalphanumeric characters and Japanese letters are stored in the outlinedata and kerning data storing unit 42. The kerning data for the lettersare calculated in advance in the minimum character region determiningapparatus 11.

Accordingly, a character string can be put close together at a highspeed because it is not required to calculated the kerning data for eachof letters.

Also, as shown in FIG. 24, it is applicable that a character stringgenerating apparatus 51 comprise an outline data and kerning datastoring unit 52 for storing pieces of outline data, a piece of top-rightkerning data, a piece of middle-right kerning data, a piece ofbottom-right kerning data, a piece of top-left kerning data, a piece ofmiddle-left kerning data and a piece of bottom-left kerning data foreach of alphanumeric characters, the character arranging unit 32 forarranging alphanumeric characters of an alphanumeric character stringaccording to the kerning data stored in the storing unit 52 to put thealphanumeric characters close together and arranging other type lettersof a character string according to the minimum character regionsobtained in the the minimum character region determining apparatus 11 toput the letters close together, and the character string outputting unit33.

Also, the squared character region Rc for a letter is partitioned intothe partitive regions Rt, Rm and Rb in the above embodiment. The numberof partitive regions is determined by considering the increase of a datacapacity required for storing the fit data and the character data foreach of the partitive regions and the increase of a processing time oncondition that letters of a character string is comfortably put closetogether. However, it is applicable that the squared character region Rcfor a letter be partitioned into two partitive regions or be partitionedinto four or more partitive regions if circumstances require.

Having illustrated and described the principles of our invention in apreferred embodiment thereof, it should be readily apparent to thoseskilled in the art that the invention can be modified in arrangement anddetail without departing from such principles. We claim allmodifications coming within the spirit and scope of the accompanyingclaims.

What is claimed is:
 1. A minimum character region determining method,comprising the steps of:preparing a letter of a character string, theletter being placed in a rectangular character region; producing a rightproportional data value indicating a right proportional position spacedapart from the letter toward a right direction and a left proportionaldata value indicating a left proportional position spaced apart from theletter toward a left direction; horizontally partitioning therectangular character region of the letter into a plurality of partitiveregions by one or more boundary lines to horizontally partition theletter into a plurality of portions of the letter; detecting one or morestarting points of one or more line segments of the letter and one moreending points of the line segments for each of the partitive regions;detecting one or more intersection points between the letter and eachboundary line for each of the partitive regions; determining one pointplaced on most right side among the starting and ending points of theline segments and the intersection points as a right fit point for eachof the partitive regions; determining one point end placed on the mostleft side among the starting and ending points of the line segments andthe intersection points as the left fit point for each of the partitiveregions; producing a right fit data value indicating a right fitposition of the right fit point for each of the partitive regions;producing a left fit data value indicating a left fit position of theleft fit point for each of the partitive regions; determining a rightminimum fit data value denoting one right fit position placed on themost right side among the right fit positions, one partitive regionrelating to the right minimum fit data value being called a rightminimum partitive region; determining a left minimum fit data valuedenoting one left fit position placed on the most left side among theleft fit positions, one partitive region relating to the left minimumfit data value being called a left minimum partitive region; setting theright proportional data value to a right kerning data value defined inthe right minimum partitive region; setting the left proportional datavalue to a left kerning data value defined in the left minimum partitiveregion; setting a prescribed right value between the right minimum fitdata value and one right fit data value for each of the partitiveregions other than the right minimum partitive region to another rightkerning data value; setting a prescribed left value between the leftminimum fit data value and one left fit data value defined for each ofthe partitive regions other than the left minimum partitive region toanother kerning data value; determining a minimum character region forthe letter of which a right side is limited by a plurality of rightkerning positions indicated by the right kerning data values for all ofthe partitive regions and a left side is limited by the left kerningpositions denoted by the left kerning data in all of the partitiveregions; and outputting or displaying the minimum character region on aprinter or a display.
 2. A method according to claim 1, in which thestep of setting a prescribed right value includes:setting the prescribedright value to a value of a midpoint between the right minimum fit datavalue and one right fit data value defined for each of the partitiveregions other than the right minimum partitive region; and the step ofsetting a prescribed left value includes:setting the prescribed leftvalue to a value of a midpoint between the left minimum fit data valueand one left fit data value defined for each of the partitive regionsother than the left minimum partitive region.
 3. A method according toclaim 1, in which the step of preparing a letter of a character stringincludes:specifying a letter of a character string which is composed ofa string of alphanumeric letters or Japanese letters.
 4. A methodaccording to claim 1, in which the step of horizontally partitioning therectangular character region of the letter includes:partitioning therectangular character region of the letter into three partitive regions.5. A minimum character region determining apparatus, comprising:outlinedata storing means for storing outline data of a letter, the letterbeing placed in a rectangular character region; proportional dataproducing means for producing right proportional data indicating a rightproportional position spaced apart from the letter toward a rightdirection and left proportional data indicating a left proportionalposition spaced apart from the letter toward a left direction accordingto the outline data of the letter stored in the outline data storingmeans; character region partitioning means for horizontally partitioningthe rectangular character region of the letter into a plurality ofpartitive regions by one or more boundary lines to horizontallypartition the letter into a plurality of portions of the letter; fitdata producing means for detecting one or more starting points of one ormore line segments of the letter, one or more ending points of the linesegments and one or more intersection points between the letter and eachboundary line for each of the partitive regions according to the outlinedata of the letter stored in the outline data storing means, determiningone point placed on the most right side among the starting and endingpoints of the line segments and the intersection points as a right fitpoint for each of the partitive regions; determining one point placed onthe most left side among the starting and ending points of the linesegments and the intersection points as a left fit point for each of thepartitive regions, producing right fit data indicating a right fitposition of the right fit point for each of the partitive regions, andproducing left fit data indicating a left fit position of the left fitpoint for each of the partitive regions; right minimum fit datadetermining means for determining right minimum fit data denoting oneright fit position placed on the most right side among the right fitpositions of the right fit data produced by the fit data producingmeans, one partitive region relating to the right minimum fit data beingcalled a right minimum partitive region; left minimum fit datadetermining means for determining left minimum fit data denoting oneleft fit position placed on the most left side among the left fitpositions of the left fit data produced by the fit data producing means,one partitive region relating to the left minimum fit data being calleda left minimum partitive region; first right kerning data setting meansfor setting the right proportional data produced by the proportionaldata producing means to right kerning data defined in the right minimumpartitive region; first left kerning data setting means for setting theleft proportional data produced by the proportional data producing meansto left kerning data defined in the left minimum partitive region;second right kerning data setting means for setting a prescribed rightvalue between a value of the right minimum fit data determined by theright minimum fit data determining means and a value of one right fitdata defined for each of the partitive regions other than the rightminimum partitive region by the fit data producing means to a value ofanother right kerning data; second left kerning data setting means forsetting a prescribed left value between a value of the left minimum fitdata value determined by the left minimum fit data determining means anda value of one left fit data value defined for each of the partitiveregions other than the left minimum partitive region by the fit dataproducing means to another left kerning data; minimum character regiondetermining means for determining a minimum character region for theletter of which a right side is limited by a plurality of right kerningpositions indicated by the right kerning data produced by the firstright kerning data setting means and the second right kerning datasetting means and a left side is limited by a plurality of left kerningpositions indicated by the left kerning data produced by the first leftkerning data setting means and the second left kerning data settingmeans; and displaying means for displaying the minimum character region.6. An apparatus according to claim 5, in which the prescribed rightvalue is set to a value of a midpoint between the right minimum fit datavalue and one right fit data value defined for each of the partitiveregions other than the right minimum partitive region in the secondright kerning data setting means, andthe prescribed left value is set toa value of a midpoint between the left minimum fit data value and oneleft fit data value defined for each of the partitive regions other thanthe left minimum partitive region in the second left kerning datasetting means.
 7. An apparatus according to claim 5, in which a letterindicated by the outline data in the outline data storing means is analphanumeric letter or a Japanese letter.
 8. An apparatus according toclaim 5, in which the number of partitive regions produced in thesquared character region partitioning means is three.
 9. A characterstring generating apparatus, comprising:outline data storing means forstoring outline data of each of letters in a character string, theletter being placed in a rectangular character region; proportional dataproducing means for producing right proportional data indicating a rightproportional position spaced apart from a letter toward a rightdirection and left proportional data indicating a left proportionalposition spaced apart from the letter toward a left direction accordingto the outline data of the letter stored in the outline data producingmeans:character region partitioning means for horizontally partitioningthe rectangular character region of the letter into a plurality ofpartitive regions by one or more boundary lines to horizontallypartition the outline data the letter stored in the outline dataproducing means into a plurality of portions of the letter; fit dataproducing means for detecting one or more starting points of one or moreline segments of the letter, one or more ending points of the linesegments and one or more intersection points between the letter and eachboundary line for each of the partitive regions according to the outlinedata of the letter stored in the outline data storing means, determiningone point placed on the most right side among the starting and endingpoints of the line segments and the intersection points as a right fitpoint for each of the partitive regions; determining one point placed onthe most left side among the starting and ending points of the linesegments and the intersection points as a left fit point for each of thepartitive regions, producing right fit data indicating a right fitposition of the right fit point for each of the partitive regions, andproducing left fit data indicating a left fit position of the left fitpoint for each of the partitive regions;right minimum fit datadetermining means for determining right minimum fit data denoting oneright fit position placed on the most right side among the right fitpositions, one partitive region relating to the right minimum fit databeing called a right minimum partitive region; left minimum fit datadetermining means for determining left minimum fit data denoting oneleft fit position placed on the most left side among the left fitpositions, one partitive region relating to the left minimum fit databeing called a left minimum partitive region;first right kerning datasetting means for setting the right proportional data produced by theproportional data producing means to right kerning data defined in theright minimum partitive region; first left kerning data setting meansfor setting the left proportional data produced by the proportional dataproducing means to left kerning data defined in the left minimumpartitive region; second right kerning data setting means for a settinga mid-point between a value of the right minimum fit data determined bythe right minimum fit data determining means and a value of one rightfit data defined for each of the partitive regions other than the rightminimum partitive region by the fit data producing means to a value ofanother right kerning data; second left kerning data setting means forsetting a mid-point between a value of the left minimum fit data valuedetermined by the left minimum fit data determining means and a value ofone left fit data value defined for each of the partitive regions otherthan the left minimum partitive region by the fit data producing meansto another left kerning data; minimum character region determining meansfor determining a minimum character region for the letter of which aright side is limited by a plurality of right kerning positionsindicated by the right kerning data produced by the first right kerningdata setting means and the second right kerning data setting means and aleft side is limited by a plurality of left kerning positions indicatedby the left kerning data produced by the first left kerning data settingmeans and the second left kerning data setting means; characterarranging means for arranging the letters of the character string, ofwhich the outline data are stored in the outline data storing means, ina line to put the letters close together on condition that the minimumcharacter regions determined for the letters in the minimum characterregion determining means are not overlapped each other; and characterstring outputting means for outputting the character string of which theletters are arranged by the character arranging means.
 10. A minimumcharacter region determining method, comprising the steps of:preparing aletter of a character string, the letter being placed in a rectangularcharacter region; producing a right proportional data value indicating aright proportional position spaced apart from the letter toward a rightdirection and a left proportional data value indicating a leftproportional position spaced apart from the letter toward a leftdirection; horizontally partitioning the rectangular character region ofthe letter into a plurality of partitive regions to horizontallypartition the letter into a plurality of portions of the letter;producing a right fit data value indicating a right fit position, atwhich a portion of the letter placed at the most right side in onepartitive region is positioned, for each of the partitive regions;producing a left fit data value indicating a left fit position, at whicha portion of the letter placed at the most left side in one partitiveregion is positioned, for each of the partitive regions; determining aright minimum fit data value denoting one right fit position placed onthe most right side among the right fit positions, one partitive regionrelating to the right minimum fit data value being called a rightminimum partitive region; determining a left minimum fit data valuedenoting one left fit position placed on the most left side among theleft fit positions, one partitive region relating to the left minimumfit data value being called a left minimum partitive region; setting theright proportional data value to a right kerning data value defined inthe right minimum partitive region; setting the left proportional datavalue to a left kerning data value defined in the left minimum partitiveregion; setting right kerning data value for each of the partitiveregions other than the right minimum partitive region to a value(0.6*P1+0.4*P2) determined by a ratio 0.6/0.4 of the right minimum fitdata value (P1) to one right fit data value (P2) defined for onepartitive region other than the right minimum partitive region; settingleft kerning data value for each of the partitive regions other than theleft minimum partitive region to a value (0.6*P3+0.4*P4) determined by aratio 0.6/0.4 of the left minimum fit data value (P3) to one left fitdata value (P4) defined for one partitive region other than the leftminimum partitive region; determining a minimum character region for theletter of which a right side is limited by a plurality of right kerningpositions indicated by the right kerning data values for all of thepartitive regions; and outputting or displaying the minimum characterregion on a printer or a display.
 11. A minimum character regiondeterminting method, comprising the steps of:preparing a letter of acharacter string, the letter being placed in a rectangular characterregion; producing a right proportional data value indicating a rightproportional position spaced apart from the lettertoward a rightdirectionand a left proportional data value indicating a leftproportional position spaced apart from the letter toward a leftdirection; horizontally partitioning the rectangular character region ofthe letter into a plurality of partitive regions to horizontallypartition the letter into a plurality of portions to the letter;producing a right fit data value indicating a right fit position, atwhich a portion placed at the most right side in one partitive region ispositioned, for each of the partitive regions; producing a left fit datavalue indicating a left fit position, at which a portion of the letterplaced at the most left side in one partitive region is positioned, foreach of the partitive regions; determining a right minimum fit datavalue denoting one right fit position placed on the most right sideamong the fit position, one partitive region relating to the rightminimum fit data value being called a right minimum patitive region;determining a left minimum fit data value denoting one left fit positionplaced on the most left side among the left fit positions, one partitiveregion relating to the left minimum fit data value being calleda leftminimum partitive region; setting the right proportional data value to aright kerning data value defined in the right minimum partitive region;setting the left proportional data value to a left kerning data valuedefined in the left minimum partitive region; expressing the right fitdata value for each partitive region by a right fit distance Drf betweenthe right fit position indicated by the right fit data value and a rightside line of the and the left side line of the rectangular characterregion; expressing left kernal data value for each of the partitiveregions other than the left minimum partitive region by a left kerningdistance Dlk between a left kerning position indicated by a left kerningdata value and the left side af the rectangular character region;setting the left kerning distance Dlk to Dlk=Dlf-(Dlf-Dlm)*0.5-(Dlm-Dlp); determing a minimum charater region fot the letter ofwhich a right side is limited by a pluality of right kerning positionsindicated by the right kerning data values for all the partitiveregions; and outputting or displaying the minimum carachter region on aprinter or a display.
 12. A minimum character region determiningapparatus, comprising:outline data storing means for storing outlinedata of a letter, the letter being placed in a rectangular characterregion; proportional data producing means for producing rightproportional data indicating a right proportional position spaced apartfrom the letter toward a right direction and left proportional dataindicating a left proportional position spaced apart from the lettertoward a left direction according to the outline data of the letterstored in the outline data storing means; character region partitioningmeans for horizontally partitioning the rectangular character region ofthe letter into a plurality of partitive regions to horizontallypartition the letter into a plurality of portions of the letter; rightfit data producing means for producing right fit data indicating a rightfit position, at which a portion of the letter placed at the most rightside in one partitive region is positioned, for each of the partitiveregions produced by the character region partitioning means according tothe outline data stored in the outline data storing means; left fit dataproducing means for producing left fit data indicating a left fitposition, at which a portion of the letter placed at the most left sidein one partitive region is positioned, for each of the partitive regionsproduced by the character region partitioning means according to theoutline data stored in the outline data storing means; right minimum fitdata determining means for determining right minimum fit data denotingone right fit position placed on the most right side among the right fitpositions of the right fit data produced by the right fit data producingmeans, one partitive region relating to the right minimum fit data beingcalled a right minimum partitive region; left minimum fit datadetermining means for determining left minimum fit data denoting oneleft fit position placed on the most left side among the left fitpositions of the left fit data produced by the left fit data producingmeans, one partitive region relating to the left minimum fit data beingcalled a left minimum partitive region; first right kerning data settingmeans for setting the right proportional data produced by theproportional data producing means to right kerning data for the rightminimum partitive region; first left kerning data setting means forsetting the left proportional data produced by the proportional dataproducing means to left kerning data for the left minimum partitiveregion; second right kerning data setting means for setting rightkerning data for each of the partitive regions other than the rightminimum partitive region to a value (0.6*P1+0.4*P2) determined by aratio 0.6/0.4 of a value (P1) of the right minimum fit data determinedby the right minimum fit data determining means to a value (P2) of oneright fit data produced by the right fit data producing means for onepartitive region other than the right minimum partitive region; secondleft kerning data setting means for setting left kerning data value foreach of the partitive regions other than the left minimum partitiveregion to a value (0.6*P3+0.4*P4) determined by a ratio 0.6/0.4 of avalue (P3) of the left minimum fit data determined by the left minimumfit data determining means to a value (P4) of one left fit data producedby the left fit data producing means for one partitive region other thanthe left rectangular character region expressing the right minimum fitdata value by a minimum right kerning distance Drm between one right fitposition placed on the most right side and the right side line of therectangular character region; expressing the right proportional datavalue by a right proportional distance Drp between the rightproportional position and the right side line of the rectangularcharacter region; expressing right kerning data value for each of thepartitive regions other than the right minimum partitive region by aright kerning distance Drk between a right kerning position indicated bythe right kerning data value and the right side line of the rectangularcharacter region; setting the right kerning distance Drk toDrk=Drf-(Drf-Drm)*0.5-(Drm-Drp); expressing the left fit data value foreach partitive region by a left fit distance Dlf between the left fitposition indicated by the left fit data value and a left side line ofthe rectangular character region; expressing the left minimum fit datavalue by a minimum left kerning distance Dlm between one left fitposition placed on the most left side and the left side line of therectangular character region; expressing the left proportional datavalue by a left proportional distance Dlp between the left proportionalposition minimum partitive region; minimum character region determiningmeans for determining a minimum character region for the letter of whicha right side is limited by a plurality of right kerning positionsindicated by the right kerning data produced by the first right kerningdata setting means and the second right kerning data setting means and aleft side is limited by a plurality of left kerning positions indicatedby the left kerning data produced by the first left kerning data settingmeans and the second left kerning data setting means; and displayingmeans for displaying the minimum character region.
 13. A minimumcharacter region determining apparatus, comprising:outline data storingmeans for storing outline data of a letter, the letter being placed in arectangular character region; proportional data producing means forproducing right proportional data indicating a right proportionalposition spaced apart from the letter toward a right direction and leftproportional data indicating a left proportional position spaced apartfrom the letter toward a left direction according to the outline data ofthe letter stored in the outline data storing means; character regionpartitioning means for horizontally partitioning the rectangularcharacter region of the letter into a plurality of partitive regions tohorizontally partition the letter into a plurality of portions of theletter; right fit data producing means for producing right fit dataindicating a right fit position, at which a portion of the letter placedat the most right side in one partitive region is positioned, for eachof the partitive regions produced by the character region partitioningmeans according to the outline data stored in the outline data storingmeans; left fit data producing means for producing left fit dataindicating a left fit position, at which a portion of the letter placedat the most left side in one partitive region is positioned, for each ofthe partitive regions produced by the character region partitioningmeans according to the outline data stored in the outline data storingmeans; right minimum fit data determining means for determining rightminimum fit data denoting one right fit position placed on the mostright side among the right fit positions of the right fit data producedby the right fit data producing means, one partitive region relating tothe right minimum fit data being called a right minimum partitiveregion; left minimum fit data determining means for determining leftminimum fit data denoting one left fit position placed on the most leftside among the left fit positions of the left fit data produced by theleft fit data producing means, one partitive region relating to the leftminimum fit data being called a left minimum partitive region; firstright kerning data setting means for setting the right proportional dataproduced by the proportional data producing means to right kerning datafor the right minimum partitive region; first left kerning data settingmeans for setting the left proportional data produced by theproportional data producing means to left kerning data for the leftminimum partitive region; second right kerning data setting means forsetting right kerning data for each of the partitive regions other thanthe right minimum partitive region on condition that a right kerningdistance Drk between a right kerning position indicated by the rightkerning data and a right side line of the rectangular character regionis set to Drk=Drf-(Drf-Drm)*0.5-(Drm-Drp), the symbol Drf denoting aright fit distance between the right fit position indicated by the rightfit data and the right side line of the rectangular character region,the symbol Drm denoting a minimum right kerning distance between oneright fit position placed on the most right side and the right side lineof the rectangular character region, and the symbol Drp denoting a rightproportional distance between the right proportional position indicatedby the proportional data producing means and the right side line of therectangular character region; second left kerning data setting means forsetting left kerning data for each of the partitive regions other thanthe left minimum partitive region on condition that a left kerningdistance Dlk between a left kerning position indicated by the leftkerning data and a left side line of the rectangular character region isset to Dlk=Dlf-(Dlf-Dlm)*0.5-(Dlm-Dlp), the symbol Dlf denoting a leftfit distance between the left fit position indicated by the left fitdata and the left side line of the rectangular character region, thesymbol Dlm denoting a minimum left kerning distance between one left fitposition placed on the most left side and the left side line of therectangular character region, and the symbol Dlp denoting a leftproportional distance between the left proportional position indicatedby the proportional data producing means and the left side line of therectangular character region; minimum character region determining meansfor determining a minimum character region for the letter of which aright side is limited by a plurality of right kerning positionsindicated by the right kerning data produced by the first right kerningdata setting means and the second right kerning data setting means and aleft side is limited by a plurality of left kerning positions indicatedby the left kerning data produced by the first left kerning data settingmeans and the second left kerning data setting means; and displayingmeans for displaying the minimum character region.